CHAPTER XXVI. 



WOUNDS — continued, 



METHODS OF REPAIR IMMEDIATE UNION PRIMARY ADHESION 



GRANULATION SECONDARY ADHESION HEALING UNDER A SCAB 



FORMATION OF THE CICATRIX, AND COMPLETION OF THE REPARA- 

 TIVE PROCESS. 



REPAIR OF WOUNDS, AND THE METHODS OF HEALING. 



Paget, in his admirable Lectures on Surgical Pathology, very 

 profoundly considers the question of the reproduction of injured 

 and lost parts; and he says — " The ability to repair the 

 damages sustained by injury, and to produce lost parts, appears 

 to belong in some measure to all bodies that have definite 

 form and construction. It is not an exclusive property of living 

 beings, for even crystals will repair themselves, when, after 

 pieces have been broken from them, they are placed in the same 

 conditions in which they were first formed. The power of 

 reproduction is exemplified in a most remarkable manner in the 

 lower form of animals, some having the power of reproducing 

 themselves from a fragment into a whole and perfect body ; in 

 others, the reproduction of a lost limb has been observed ; but 

 in the animals we have to deal with this power is limited to the 

 reproduction of tissues of three classes. 



" 1st. To those which are. formed entirely by nutritive repeti- 

 tion, such as the blood and epithelia. 



" 2d. To those which are of lowest organization, and (which 

 seem of more importance) of lowest chemical characters — the 

 gelatinous tissues, the connective, and the bones. 



" M. To those which are inserted in other tissues, not as 

 essential to their structure, but as accessories, as connecting or 

 incorporating them with the other structures of vegetative or 

 animal life, such as nerve-fibres and blood-vessels. 



